U.S. Pat. Nos. 5,005,883, 5,127,687, 4,802,700, 5,347,689, 5,413,393, 6,265,973 ('973), 6,407,666 ('666), 6,097,306 ('306), 7,239,238 ('238) and others are commonly owned and disclose various seals including electronic seals ('973, '666 and '238)(a programmable seal '306) including shackles made of stranded metal wire ('238), steel bolts ('666 and '973) and still other arrangements, all incorporated by reference herein.
Of interest are US Publication 2009/0066503 filed Nov. 29, 2007 in the name of Lien-Feng Lin published Mar. 12, 2009 and claiming priority on TW 096133563 Sep. 7, 2007 and TW 096135554 Sep. 21, 2007 and US Publication 2009/0072554 filed Sep. 11, 2008 in the name of Paul. R. Arguin published Mar. 19, 2009 claiming priority on US provisional application No. 60/993,599 filed Sep. 13, 2007, all incorporated by reference herein in their entirety.
The Lin publication discloses a system for monitoring containers with seals and includes a seal, an electronics monitoring device and a communications center. The monitoring device is connected to the seal which locks the doors. The device detects the seal status and also detects the seal's position using a GPS locating system communicating the data via cell phone technology. The related seal data is sent to a communications center which determines the position of the related container and whether the doors have been tampered with and opened. The seal contains RFID data identifying the seal. A plug is inserted into a socket and detained by a detaining device in the socket. The seal plug is first inserted through a buckle of a door engaged with a buckle of another door, through the seal shell containing the electronics and then into the socket. The monitoring system communicates with a communications center, preferably a mobile phone such as a GPS cell phone through one or more stations and communicates with the communication center through GSM stations.
A detection unit detects the presence of the plug using a micro-switch, a spring-biased switch, or a reed switch. When the plug is torn or cut, the switch detects this and changes the electrical status. In the alternative, a photo-breaker may be used to optically detect the presence of the plug. When the plug is removed by cutting or tearing, the optical path is no longer broken to the optical detector and the seal's tampered state is indicated.
When a reed switch is used, a magnet is also required. The seal plug may be designed to be reused and inserted and pulled from the socket many times. Therefore, in this mode the plug is not permanently locked to the socket.
The Arguin publication discloses a pin (bolt) style cargo seal with a removable tracking module. A pin is inserted into a barrel portion, which is removeably secured to a tracking module wherein the structure coupling the tracking module electronically and mechanically to the barrel and pin is not shown or described. The pin is fixed to the barrel and must be cut with bolt cutters or the like to remove the pin from the barrel. The tracking module includes an optional RFID component which deactivates upon tampering or cutting the bolt. The electronics in the tracking module includes an RFID circuit, which may be active, passive or semi-passive. The electronics includes GPS and cellular technology. The cellular technology is typically Global System for Mobil Communications (GSM) or can be Code Division Multiple Access (CDMA) or other technologies including General Packet Radio Service (GPRS). The GSM system uses TDMA for communication between a mobile phone and a base station, wherein several callers may share the same channel. GPRS can be used for Wireless Application Protocol (WAP) access, short Message Service (SMS), Multimedia Messaging Service (MMS) and internet communication services such as email and World Wide Web. The tracking module includes software with scanning of RFID to verify the seal is valid and not tampered with. However, no electronics structure is shown electrically connecting the tracking module to the pin (bolt) for detecting the state of the pin (bolt) or how the tamper state of the bolt is detected.
Containers are widely employed in the cargo industry. The containers have doors which are locked shut with hasps and secured with locking seals, particularly employing bolts. The bolts typically are steel having a head and shank which is locked to a locking device comprising a body having a shank locking mechanism. Such a device and mechanism are shown for example in U.S. Pat. No. 4,802,700. When the shank is inserted into the body, a locking collet or other structural arrangement permanently locks the shank to the body. Further examples of such seals and locking devices are included in the above referenced US patents.
Cargo containers are shipped via land, sea and air transportation. Hundreds of containers may be on a single ship. When the containers are unloaded they may be subject to tampering and vandalism. It is important that such tampering be immediately noted to preclude theft of valuable cargo. To assist in such theft and tampering prevention, prior art seals are assigned serial numbers. These seals are then assigned and locked to the assigned container. The serial number, container number, the carrier, and the location of the cargo are entered into a local computer. The entry then is manually made to show that the container is being shipped out of that location. Should a seal be tampered with, this most likely will occur at a different time and different location.
An electronic tagging device is commercially available that is programmable and which transmits information that is programmed, such as tagging identification serial numbers and other information as desired. This is referred to as radio frequency identification (RFID) which is well known in the art. Generally, an RFID tag will have a radio frequency (RF) transmitter, an RF receiver, an RF modulator, and a memory. The memory retains the digital code manifesting the identification number. The RF modulator extracts the digital code representing the identification number as a modulated signal, which is applied to the RF transmitter. The RF receiver receives interrogation and control signals which manifest a request for the identification number.
Such systems provide security tagging for high value merchandise as it is transferred from the manufacturer to the consumer. Other applications include tagging of animals, humans and vehicles such as trucks and their cargo containers. Other applications include automatic toll collection systems.
FIG. 18 illustrates a prior art RFID communication system 214′. The system includes an interrogator 216′ and an RFID tag 218′. The interrogator 216′ includes a host controller 220′ (a microprocessor) to process received information from the RFID tag 218′ via antenna 222′ and receiver 224′. To retrieve information from the RFID tag 218′, the host controller 220′ generates an interrogation command signal which is transmitted by transmitter 226′ and antenna 228′ as signal 230′. The tag 218′ transmits RFID signal 232′ via antenna 234′ in response to receipt of the interrogation command signal 230′. The receiver 224′ receives the signal 232′ via antenna 222′. The signal 232′ manifests the identification number of the tag 218′.
The RFID tag 218′ has an antenna 236′ and a receiver 238′ to receive the interrogation command signal 230′ from the interrogator 216′. The receiver 238′ transfers the received command signal to a controller 240′. The controller 240′ interprets the command and extracts the corresponding identification number (ID) from memory 242′. The extracted identification number is then transferred by the controller 240′ to transmitter 244′ which transmits the ID to antenna 234′ which broadcasts the signal 232′.
In active RFID tags, power 246′ is provided by a battery system. In passive systems, the power is induced from the received signal. The signal 232′ transmitted by the RFID tag 218′ is modulated back scatter of the original signal transmitted by the interrogator 216′.
The controller 240′ may have an interface, not shown, to receive data from external transponders such as temperature sensors, pressure sensors, global positioning sensing and other telemetric measurement data.
Commonly owned U.S. Pat. No. 6,265,973 discloses an electronic security seal which is used with a steel bolt having an insulating coating thereon and a metallic coating on the insulating coating. The metallic coating is in ohmic contact with the bolt head to form a continuous conductor with the bolt shank. A pair of electrical contacts engage the shank and metallic coating to form a circuit path between the contacts. The contacts are coupled to the circuit for sensing a break in the path manifesting a tampered condition wherein the bolt may have been severed opening the path.
U.S. Pat. No. 7,239,238 discloses an electronic security seal using a stranded cable shackle having an internal conductor whose resistance manifests the tampered state of the device and which resistance is monitored by the circuit. This exhibits a similar problem as the '973 patent discussed above. When the shackle is destroyed to open the seal, the entire assembly needs to be discarded. This too is costly.
U.S. Pat. No. 6,407,666 discloses an electrical connector for a cylindrical member such as a steel bolt. Disclosed are a pair of spaced apart rings or similar shaped contacts that make contact with the bolt for completing the circuit between the bolt and sensing circuit. The circuit is for generating a signal manifesting a tampered state of the bolt when the bolt is severed breaking the circuit. The bolt in this device if severed to open the seal results also in the entire assembly being discarded, a costly system.
U.S. Pat. No. 7,042,354 (which includes a family of patents U.S. Pat. Nos. 6,778,083, 6,791,465, and US publication Nos. 2006/0170560 and 2006/0109111) discloses a tamper resistant electronic security seal. The seal comprises a bolt shank, a head which houses the seal circuitry and a bolt locking device which mates with a groove in the bolt shank similar to prior art locking devices. Such a device is shown for example in U.S. Pat. Nos. 4,802,700 and 5,005,883. To open the seal sealed with such a bolt, the bolt needs to be severed and the entire assembly is discarded as the locking device is permanently attached to the bolt via a groove in the bolt. This presents the same problem of cost in using this seal as the seals described above.
U.S. Pat. No. 6,747,558 ('558) to Thorne describes an electronic bolt type security seal using two adjacent magnetic fields as bolt sensors. The fields are generated by two corresponding coils located in corresponding two adjacent arms extending from an electronic seal module housing the rest of the circuitry. The bolt passes through the arms and coils. A locking device is attached to the bolt to secure the bolt to a hasp. When the bolt is severed, the seal module and arms may be reused. However, this design is different than the commercially available modules of the prior art seals discussed above, which seals require that the electronic modules be discarded when the bolts are opened and also discarded. This patent does not solve the problem with those other prior art electronic bolt seals, because it uses a different circuitry than the prior art circuitry commonly used.
The use of a low cost seal system represents a problem not addressed by U.S. Pat. No. 6,747,558. The relatively small coil portion of the circuitry (not used in conventional seal tamper evident circuits) is housed in arms separate from the electronics circuitry housing for the majority of the involved circuits etc. That is, the detection circuitry is not entirely within a single housing and makes the system more costly than a single module system.
Further, the bolt is not part of the circuit, but is used only to transmit magnet fields somewhat in a similar manner to a switch. When the bolt is present the magnetic field of one coil is transmitted to a second coil of the detection circuit, which coil normally cannot detect the field without the bolt being present. The detection circuit detects the magnetic field in this second coil. The two coils are in separate housings that are attached to an arm. The arm is attached to the main circuit module housing. When the bolt is inserted through the two coils it is also inserted into the hasp for locking the hasp. The two coils form a part of the detection circuit, but are in costly separate housings. This is more costly than a single housing as desired by the present inventors.
The Lin publication does not use a bolt that completes the detection circuit and does not form a part of the detection circuit, but rather includes switches and optical devices, which mechanically open and close the circuit in response to the presence of a bolt. No circuit is employed in the disclosed bolts, which are only used to physically activate a switch when present. When the bolt is absent, the switches have one on/off state manifesting the tampered unlocked state and when the bolt is present, the switches switch to their other state manifesting the normal locked condition.
The patent '558 also describes seals with reusable housings and disposable bolts. These seals are not described as being electronic. In this description, an end of the bolt is locked inside the seal housing not otherwise described. To open the seal the bolt is cut with a bolt cutter. The end of the bolt inside the housing can then be removed by sliding the remaining bolt portion out of the housing in the same direction as the insertion direction. This seems to require the housing to be opened to access the bolt fragment to remove it from the housing. No drawing or reference document is cited by the '558 patent showing the particular device being described therein. While this device may solve the problem of providing a reusable housing, it does not seem to be directed to electronic seals.
The cited circuit housing described by '558 appears to be needed to be opened to remove the remnant of the cut bolt from inside the housing. In electronic seals, opening the housing is not desirable as the electronic circuitry inside the housing may become contaminated and unusable.
U.S. Pat. No. 5,152,650 discloses an electrically conductive synthetic resin bolt.
German document DE 010322648 discloses plastic fixing screws for door lock cylinders with embedded conductive strips to operate an alarm if the bolt is deformed by tampering.
Int'l publication No. WO 2006/074518 discloses a transponder bolt seal and a housing for a transponder. An actuator is actuated upon engagement of the sealing mechanism to render the transponder operable. Insertion of a locking member into a receptacle causes the actuator to actuate. The device has a curved shape with a convex side facing away from the sealing mechanism and a concave side facing the sealing mechanism. A cover is used and if the bolt is removed, the cover is damaged, and thus this seal is not reusable if the bolt is removed to open the seal. This application does not address the need for a less costly seal system employing a reusable electronic seal module for use with conventional bolts and locking devices.